Welcome to Scholarpedia, the peer-reviewed open-access encyclopedia written by scholars from all around the world. Scholarpedia feels and looks like Wikipedia -- the free encyclopedia that anyone can edit. Indeed, both are powered by the same program -- MediaWiki. Both allow visitors to review and modify articles simply by clicking on the edit this article link. However, Scholarpedia differs from Wikipedia in some very important ways: Each article is written by an expert. Each article is anonymously peer reviewed to ensure accurate and reliable information. Each article has a curator -- typically its author -- who is responsible for its content. Any modification of the article needs to be approved by the curator before it appears in the final, approved version. Herein also lies the greatest difference between Scholarpedia and traditional print media: although the initial authorship and review are similar to a print journal so that Scholarpedia articles could be cited, articles are not frozen and outdated, but dynamic, subject to an ongoing process of improvement moderated by their curators. This allows Scholarpedia to be up-to-date, yet maintain the highest quality of content.